Which one of the following best illustrates a primary reinforcer? a. water when you're thirsty b. the sight of a chocolate meringue pie c. money d. a warm smile from your boss

Why did many members of congress oppose president lincoln’s plan for reconstruction? a. they believed that freed blacks had gained too much power. b. they thought that the plan was too harsh on confederate sympathizers in the north. c. they thought that the president had overstepped his powers.

In 1990, the average income for an american worker was $1,518 per month. in 2000, the average income for an american worker was $2,632 per month. during this time period, a basket of necessities (food, housing, etc.) increased from $657 per month in 1990 to $1,402 per month in 2000. the real value of income ▼ increased decreased over that 10-year period.

This term refers to the number of people per unit area (usually a kilometer or a mile). this could refer to the number of people per square mile in a city, a county, a province, a state, or a nation.